Garbage In, Garbage Out: FileSlinger™ Backup Reminder 07-11-08

I have a friend(?) whose chosen backup strategy is to e-mail me copies of her important files and BCC me on her important e-mail messages. I did not volunteer for this service, and I’m not recommending it to anyone as a particularly good approach to backing up your data. It beats having no backups at all, and it’s one of the few options available to my friend(?), whose own computer isn’t connected to the Internet and who does almost everything on a U3 data stick at public library computers (which tend to be designed not to let U3 data sticks work properly, or run any programs).

So she e-mails me files and I save them into a folder for her, where they get backed up with the rest of my documents. I then usually delete the attachments from Outlook, because my main PST file is big enough as it is.

And I don’t usually pay any more attention to the files themselves than any backup program would. They get scanned for viruses on the way into Outlook, and I don’t have the time or inclination to check the content or format of these files (usually Word documents).

But the other day I happened to notice something. My friend(?) was sending documents to some prospects, and one of the Microsoft Word files was only 150 bytes. When was the last time you saw a Microsoft Word doc that was less than 1K in size? Even a flat text file is longer than that if it has any content.

So I tried opening the file, and sure enough, there was nothing in it. I have no idea how this happened; some error in saving the file, perhaps. My friend(?) is kind of jinxed when it comes to computers, as if they weren’t capable of creating problems all by themselves.

I told her about the problem. Naturally, she freaked out. Then she asked me whether I had an earlier, uncorrupted version of that file. Fortunately for her, I did. (More fortunately, she had given it a different file name, so it didn’t get overwritten by the 1K file.) So I e-mailed that back to her.

But it got me to thinking about the first thing I ever learned about computers—from reading science fiction, before I’d ever touched a computer myself.

Garbage In, Garbage Out.

If you make multiple backups of a corrupted file, then all you have is several useless files instead of one. Even backup software that verifies your data is only making sure that the copy is the same as the original. You’re the one who has to make sure the original is worth copying.

Now, most of us have no reason to think our files might be corrupt. If the file was fine the last time you used it, then there’s not likely to be anything to worry about. But if the document is critically important, you should check it before you either back it up or submit it to a client.

This is especially true if you’ve been having any kinds of problems with your computer, your software, or your storage. My friend(?) has been having lots of trouble with corrupted files lately. Whatever the cause (and I’m not really in a position to guess), that’s a sign that she needs to check her files before she sends them to me or anyone else—but especially before she sends them to me, if she’s counting on me to be able to provide her with intact files when she needs them.

Checking all your files before every backup job isn’t practical. But some files are more important to save than others. Before you take your jewelry over to the safe deposit box, you might want to be sure it’s not counterfeit.

And don’t even think about e-mailing me your documents for safekeeping.